Identification of carotenoids in Erwinia herbicola and in a transformed Escherichia coli strain.
The yellow pigments of Erwinia herbicola Eho 10 and of a transformed Escherichia coli LE392 pPL376 have been identified as carotenoids. HPLC separation, spectra and in some cases mass spectroscopy demonstrated the presence of phytoene (15-cis isomer), beta-carotene (all-trans, 9-cis and 15-cis), beta-cryptoxanthin ( = 3-hydroxy beta-carotene), zeaxanthin (3,3'-dihydroxy beta-carotene) and corresponding carotene glycosides. In addition, lycopene and gamma-carotene accumulated in the presence of the inhibitor 2-(4-chlorophenylthio)-triethylamine.HCl. Carotenoid content in the transformed E. coli was two-fold higher than in E. herbicola. The pattern of the carotenoids was similar in the two organisms. Inactivation of the katF gene in E. coli resulted in an 85% lowering of carotenoid formation, as did the addition of 0.5% glucose to the medium. Suppression of carotenoid formation by inactivation of the katF gene lowered, but did not abolish, the protection offered by carotenoids against inactivation by alpha-terthienyl plus near-ultraviolet light (320-400 nm).
Sandmann
G
G
Lehrstuhl für Physiologie und Biochemie der Pflanzen, Universität Konstanz, F.R.G.
Woods
W S
WS
Tuveson
R W
RW
D002338:Carotenoids / Q000032:analysis* / Q000096:biosynthesis / Q000235:genetics; D002851:Chromatography, High Pressure Liquid; D004885:Erwinia / Q000032:analysis* / Q000235:genetics / Q000378:metabolism; D004926:Escherichia coli / Q000032:analysis / Q000235:genetics*; D014169:Transformation, Bacterial
D002338:Carotenoids